DNA topoisomerase IIβ: A player in regulation of gene expression and cell differentiation

► DNA topoisomerases II are enzymes which cleave both strands of DNA causing relaxation, decatenation and unknotting. ► In vertebrates there are two forms of topoisomerase II (α and β) with distinct functions. ► Topoisomerase IIα is necessary for cellular replication, while the β isoform is implicated mainly in transcription regulation and tissue differentiation.